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The Paley-Wiener Theorem for General Weighted Hardy Spaces on Tube Domains
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作者 HUANG Yun ZHANG Dawei 《应用数学》 北大核心 2025年第3期841-849,共9页
In this paper,the Paley-Wiener theorem is extended to the analytic function spaces with general weights.We first generalize the theorem to weighted Hardy spaces Hp(0<p<∞)on tube domains by constructing a sequen... In this paper,the Paley-Wiener theorem is extended to the analytic function spaces with general weights.We first generalize the theorem to weighted Hardy spaces Hp(0<p<∞)on tube domains by constructing a sequence of L^(1)functions converging to the given function and verifying their representation in the form of Fourier transform to establish the desired result of the given function.Applying this main result,we further generalize the Paley-Wiener theorem for band-limited functions to the analytic function spaces L^(p)(0<p<∞)with general weights. 展开更多
关键词 Paley-Wiener theorem Fourier transform Weighted Hardy space Tube domain
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Minimum safe thickness of rock plug in karst tunnel according to upper bound theorem 被引量:14
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作者 YANG Zi-han ZHANG Jia-hua 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第9期2346-2353,共8页
High pressure and water-bearing caverns ahead of a karst tunnel face tend to cause geological disasters, such as water and mud bursts. So, the determination of safe thickness of the reserved rock plug is a key technic... High pressure and water-bearing caverns ahead of a karst tunnel face tend to cause geological disasters, such as water and mud bursts. So, the determination of safe thickness of the reserved rock plug is a key technical problem to be solved for karst tunnel construction. Based on the Hoek-Brown nonlinear failure criterion, the minimum safe thickness of rock plug was investigated in the light of the limit analysis theory. On the basis of the proposed failure mode, the expression of the minimum thickness for rock plug was obtained by means of upper bound theorem in combination with variational principle. The calculation results show the influence of each parameter on safe thickness and reveal the damage range of rock plug. The proposed method is verified by comparing the results with those of the drain cavern of Maluqing Tunnel. The research shows that with the increase of compressive strength and tensile strength as well as constant A of Hoek-Brown criterion, the safe thickness decreases, whereas with the increase of cavern pressure, tunnel diameter, and constant B from Hoek-Brown criterion, the safe thickness increases. Besides, the tensile strength, or constants A and B affect the shear failure angle of rock plug structure, but other parameters do not. In conclusion, the proposed method can predict the minimum safe thickness of rock plug, and is useful for water burst study and prevention measures of tunnels constructed in high-risk karst regions. 展开更多
关键词 karst tunnels rock plug minimum safe thickness upper limit theorem failure mode
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Force analysis of pile foundation in rock slope based on upper-bound theorem of limit 被引量:13
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作者 赵明华 刘建华 +1 位作者 刘代全 汪优 《Journal of Central South University of Technology》 EI 2008年第3期404-410,共7页
Based on the characteristic that the potential sliding surfaces of rock slope are commonly in the shape of either line or fold line,analysis thought of conventional pile foundation in the flat ground under complex loa... Based on the characteristic that the potential sliding surfaces of rock slope are commonly in the shape of either line or fold line,analysis thought of conventional pile foundation in the flat ground under complex load condition was applied and the upper-bound theorem of limit analysis was used to compute thrust of rock layers with all possible distribution shapes. The interaction of slope and pile was considered design load in terms of slope thrust,and the finite difference method was derived to calculate inner-force and displacement of bridge pile foundation in rock slope under complex load condition. The result of example shows that the distribution model of slope thrust has certain impact on displacement and inner-force of bridge pile foundation. The maximum displacement growth rate reaches 54% and the maximum moment and shear growth rates reach only 15% and 20%,respectively,but the trends of inner-force and displacement of bridge pile foundation are basically the same as those of the conventional pile foundation in the flat ground. When the piles bear the same level lateral thrust,the distribution shapes of slope thrust have different influence on inner-force of pile foundation,especially the rectangle distribution,and the triangle thrust has the smallest displacement and inner-force of pile foundation. 展开更多
关键词 pile foundation rock slope inner-force calculation finite difference method upper-bound theorem of limit analysis
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NONEMPTY INTERSECTION THEOREMS AND SYSTEM OF GENERALIZED VECTOR EQUILIBRIUM PROBLEMS IN PRODUCT G-CONVEX SPACES 被引量:3
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作者 丁协平 《应用数学和力学》 EI CSCD 北大核心 2004年第6期563-571,共9页
By using an existence theorems of maximal elements for a family of set-valued mappings in G-convex spaces due to the author, some new nonempty intersection theorems for a family of set-valued mappings were established... By using an existence theorems of maximal elements for a family of set-valued mappings in G-convex spaces due to the author, some new nonempty intersection theorems for a family of set-valued mappings were established in noncompact product G-convex spaces. As applications, some equilibrium existence theorems for a system of generalized vector equilibrium problems were proved in noncompact product G-convex spaces. These theorems unify, improve and generalize some important known results in literature. 展开更多
关键词 集值映象组 非空交定理 广义矢量平衡问题组 乘积G凸空间
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Decision Making as Theorem Proving
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作者 Zhu, Mingyuan Wang, Chengwei 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1993年第1期3-32,共30页
We present a method for using type theory to solve decision making problem. Our method is based on the view that decision making is a special kind of theorem proving activity. An isomorphism between problems and types... We present a method for using type theory to solve decision making problem. Our method is based on the view that decision making is a special kind of theorem proving activity. An isomorphism between problems and types, and solutions and programs has been established to support this view which is much similar to the Curry-Howard isomorphism between propositions and types, and proofs and programs. To support our method, a proof development system called PowerEpsilon has been developed, and the synthesis of a decision procedure for validity of first-order propositional logic is discussed to show the power of the system. 展开更多
关键词 Computer programming languages Computer software Decision theory Formal logic Mathematical transformations Recursive functions theorem proving
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Application of Sturm Theorem in the Global Controllability of a Class of High Dimensional Polynomial Systems
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作者 XU Xueli LI Qianqian SUN Yimin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第5期1049-1057,共9页
In this paper, the global controllability for a class of high dimensional polynomial systems has been investigated and a constructive algebraic criterion algorithm for their global controllability has been obtained. B... In this paper, the global controllability for a class of high dimensional polynomial systems has been investigated and a constructive algebraic criterion algorithm for their global controllability has been obtained. By the criterion algorithm, the global controllability can be determined in finite steps of arithmetic operations. The algorithm is imposed on the coefficients of the polynomials only and the analysis technique is based on Sturm Theorem in real algebraic geometry and its modern progress. Finally, the authors will give some examples to show the application of our results. 展开更多
关键词 Global controllability high dimensional systems number of sign variations polynomial Sturm theorem.
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A method based on Chinese remainder theorem with all phase DFT for DOA estimation in sparse array
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作者 CAO Chenghu ZHAO Yongbo +2 位作者 PANG Xiaojiao XU Baoqing CHEN Sheng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第1期1-11,共11页
This paper takes further insight into the sparse geometry which offers a larger array aperture than uniform linear array(ULA)with the same number of physical sensors.An efficient method based on closed-form robust Chi... This paper takes further insight into the sparse geometry which offers a larger array aperture than uniform linear array(ULA)with the same number of physical sensors.An efficient method based on closed-form robust Chinese remainder theorem(CFRCRT)is presented to estimate the direction of arrival(DOA)from their wrapped phase with permissible errors.The proposed algorithm has significantly less computational complexity than the searching method while maintaining similar estimation precision.Furthermore,we combine all phase discrete Fourier transfer(APDFT)and the CFRCRT algorithm to achieve a considerably high DOA estimation precision.Both the theoretical analysis and simulation results demonstrate that the proposed algorithm has a higher estimation precision as well as lower computation complexity. 展开更多
关键词 direction of arrival(DOA) wrapped phase closedform robust Chinese remainder theorem(CFRCRT) all phase discrete Fourier transfer(APDFT)
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The Engel's theorem for braided lie algebras
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作者 SHANGGUAN Ling xi,WANG Shuan hong (College of Mathematics and Information Science, Henan Normal University,Xinxiang 453002, China) 《河南师范大学学报(自然科学版)》 CAS CSCD 2003年第3期119-119,共1页
关键词 辫子李代数 Engel定理 YETTER-DRINFELD范畴 群论
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Converse Lyapunov Theorem of Input-to-State Stability for Time-delay Systems
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作者 ZHU Qiao HU Guang-Da 《自动化学报》 EI CSCD 北大核心 2010年第8期1131-1136,共6页
关键词 时滞系统 自动化系统 泛函理论 稳定性
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矩阵乘法“正则化-滤波-重采样”快速算法
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作者 丁广太 刘通 +2 位作者 支小莉 武频 童维勤 《应用科学学报》 北大核心 2026年第2期297-315,共19页
聚焦大矩阵乘法的精确算法、近似算法在速度、精度和效率方面的优势折衷问题,提出一种基于正则化、滤波、重采样技术的面向稠密矩阵乘法快速算法。基于采样定理,建立矩阵与其对应的模拟函数之间的正则化关系,进而引入滤波、重采样环节,... 聚焦大矩阵乘法的精确算法、近似算法在速度、精度和效率方面的优势折衷问题,提出一种基于正则化、滤波、重采样技术的面向稠密矩阵乘法快速算法。基于采样定理,建立矩阵与其对应的模拟函数之间的正则化关系,进而引入滤波、重采样环节,实现精确算法和近似算法的折衷机制。为追求较高的综合效率,研究了该算法的适用范围和条件,尤其是算法精度与矩阵元素数据统计特性的关系。采用独立同分布随机数发生器等方法生成的矩阵进行了数据实验,表明算法能够实现折衷目标。 展开更多
关键词 矩阵乘法 快速算法 采样定理 正则化
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消费者社会学习视角下的在线产品定价研究——以在线评论为例
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作者 刘旭旺 张玉洁 +1 位作者 齐微 雒兴刚 《系统管理学报》 北大核心 2026年第2期332-347,共16页
电商平台蕴藏的丰富数据资源可为消费者提供决策参考,是影响消费者购买行为的重要因素;同时,合理利用产品数据资源也有助于在线零售商优化定价策略。本文从消费者社会学习视角出发,基于期望效用理论,考虑消费者在购买决策中通过逐条浏... 电商平台蕴藏的丰富数据资源可为消费者提供决策参考,是影响消费者购买行为的重要因素;同时,合理利用产品数据资源也有助于在线零售商优化定价策略。本文从消费者社会学习视角出发,基于期望效用理论,考虑消费者在购买决策中通过逐条浏览在线评论来加强产品认知,运用锚定效应与贝叶斯规则量化认知更新过程,构建产品收益定价模型。借助深度学习方法和Python爬虫技术,对评论文本进行四分类情感分析,研究正负评论信息排列顺序与消费者“决策临界值”对消费者认知、产品定价、销量与利润的影响。研究结果表明:不同于传统观点,相较于零评价,少量、适度且不连续出现的负面信息反而有利于产品的定价与营销。本研究可为在线零售商基于数据驱动的产品定价决策与运营管理提供理论基础与决策支持。 展开更多
关键词 在线产品定价 社会学习 锚定效应 深度学习 贝叶斯规则
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Infinitely Many Negative Energy Solutions for Sublinear Schr¨odinger-Poisson System
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作者 CHENG Rong WU Xiao 《应用数学》 北大核心 2026年第2期564-572,共9页
In this paper,we consider a Schr¨odinger-Poisson system with sublinear nonlinearity.The growth of nonlinearity depends on potential function and a bounded function.We first obtain the existence of nontrivial solu... In this paper,we consider a Schr¨odinger-Poisson system with sublinear nonlinearity.The growth of nonlinearity depends on potential function and a bounded function.We first obtain the existence of nontrivial solution sequence with negative energy for the system via a variant Clark’s theorem.Then we get the asymptotical property of the solution sequence by L∞norm. 展开更多
关键词 Variational method Schr¨odinger-Poisson system Multiple solutions Clark’s theorem ITERATION
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McKean-Vlasov Backward Stochastic Differential Equations with Weak Monotonicity Coefficients
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作者 FU Zongkui FEI Dandan GUO Shanshan 《应用数学》 北大核心 2026年第1期98-107,共10页
This paper deals with Mckean-Vlasov backward stochastic differential equations with weak monotonicity coefficients.We first establish the existence and uniqueness of solutions to Mckean-Vlasov backward stochastic diff... This paper deals with Mckean-Vlasov backward stochastic differential equations with weak monotonicity coefficients.We first establish the existence and uniqueness of solutions to Mckean-Vlasov backward stochastic differential equations.Then we obtain a comparison theorem in one-dimensional situation. 展开更多
关键词 McKean-Vlasov backward stochastic differential equation Weak monotonicity condition Comparison theorem
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山区路基局部加筋作用对半挖半填边坡稳定性的影响
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作者 张飞 钱子晗 +1 位作者 贾世林 苏贤 《河海大学学报(自然科学版)》 北大核心 2026年第2期170-176,共7页
针对山区半挖半填路基边坡受降雨和裂缝影响极易发生失稳滑动破坏的问题,利用土工合成材料加筋土技术对边坡进行局部加固,并基于极限分析上限定理建立了考虑孔隙水压力作用下半挖半填边坡的局部加筋稳定性计算公式,通过参数分析揭示了... 针对山区半挖半填路基边坡受降雨和裂缝影响极易发生失稳滑动破坏的问题,利用土工合成材料加筋土技术对边坡进行局部加固,并基于极限分析上限定理建立了考虑孔隙水压力作用下半挖半填边坡的局部加筋稳定性计算公式,通过参数分析揭示了局部加筋作用对边坡稳定性及弱化系数对破坏模式的影响规律。结果表明:半挖半填边坡稳定所需加筋力随着填方坡度、孔隙水压力的增大而增大,而随着加筋深度、原始坡度的增大而减小;局部加筋深度增大会显著提升边坡稳定性,但需要额外考虑可能发生的平动破坏,当孔隙水压力较大时则需考虑转动破坏。 展开更多
关键词 半挖半填边坡 加筋土 孔隙水压力 极限分析 上限定理
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贝叶斯方法的基本原理及其哲学意蕴
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作者 陈晓平 《哲学分析》 北大核心 2026年第1期155-168,199,共15页
贝叶斯方法现已成为一种新的科学范式,尤其体现于当前迅速发展的人工智能领域,它为AI系统提供了处理不确定性和动态更新概率的推理框架。从基本原理上讲,贝叶斯定理为人们从验前概率过渡到验后概率提供了逻辑依据,成为人们根据经验证据... 贝叶斯方法现已成为一种新的科学范式,尤其体现于当前迅速发展的人工智能领域,它为AI系统提供了处理不确定性和动态更新概率的推理框架。从基本原理上讲,贝叶斯定理为人们从验前概率过渡到验后概率提供了逻辑依据,成为人们根据经验证据来改变置信度的理性指导。然而,贝叶斯定理本身的合理性何在?这是休谟的归纳问题在贝叶斯方法中的体现,具体呈现为贝叶斯条件化规则的合理性问题。对此可提出“最小初始概率原则”给以回答。贝叶斯方法在科学推理的应用上,一个显著方面是用多理论检验模型取代传统的单理论检验模型即假设—演绎法,这不仅符合科学史的实际案例,而且通过“意见收敛定理”得到理论上的辩护。意见收敛定理的前提条件是可交换性,对之加以分析和澄清,可使该定理的应用范围从简单的重复独立试验扩展到复杂的科学验证。 展开更多
关键词 贝叶斯方法 假设—演绎法 意见收敛定理 归纳问题 贝叶斯条件化规则
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三维稳态向列型液晶系统的Liouville型定理
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作者 王静 别群益 曹志杰 《应用数学》 北大核心 2026年第1期22-31,共10页
本文研究三维稳态向列型液晶系统的Liouville型定理.利用能量估计方法,证明了若光滑解(u,w,P)满足一些适当条件,则该系统仅有唯一解u=0,▽w=0.本文将Jarrin(2020)的结果推广到混合局部Morrey空间.
关键词 向列型液晶系统 LIOUVILLE型定理 混合局部Morrey空间
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覆冰输电导线起舞概率研究
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作者 王泽宇 王涛 +2 位作者 李正良 吕大刚 谭忆秋 《振动.测试与诊断》 北大核心 2026年第1期132-138,220,221,共9页
针对覆冰输电导线舞动问题,基于概率密度演化法,提出了一种覆冰输电导线起舞概率分析方法。首先,建立了基于临界风速的覆冰输电导线起舞功能函数,结合具有3个平动自由度与1个扭转自由度的三结点索单元的有限元模型与李雅普诺夫稳定性定... 针对覆冰输电导线舞动问题,基于概率密度演化法,提出了一种覆冰输电导线起舞概率分析方法。首先,建立了基于临界风速的覆冰输电导线起舞功能函数,结合具有3个平动自由度与1个扭转自由度的三结点索单元的有限元模型与李雅普诺夫稳定性定理,求解了覆冰输电导线起舞临界风速;其次,基于概率密度演化法,发展了一种覆冰输电导线起舞概率评估框架,并进行覆冰输电导线起舞概率的计算与分析;最后,获得了某单跨覆冰导线算例的起舞概率并进行了参数分析。分析结果表明:本研究方法可准确计算该单跨输电导线的起舞概率,在计算效率上相比拉丁超立方抽样-蒙特卡洛模拟法(Latin hypercube sampling-Monte Carlo simulation,简称LHS-MCS)具有显著优势;档距、初始水平张力与初始风攻角对该单跨输电导线的起舞概率影响较大。 展开更多
关键词 输电线路 索单元 舞动 李雅普诺夫稳定性定理 概率密度演化法
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RISC-V SBI固件安全启动过程的形式化验证
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作者 杨叶倩 戴鸿君 《计算机研究与发展》 北大核心 2026年第3期768-781,共14页
RISC-V SBI(supervisor binary interface)标准定义了RISC-V架构硬件与操作系统的接口规范。相比x86和ARM固件,SBI固件更合规、可靠;但现有版本仍存在启动正确性未验证、PMP(physical memory protection)物理地址访问等安全漏洞。为此,... RISC-V SBI(supervisor binary interface)标准定义了RISC-V架构硬件与操作系统的接口规范。相比x86和ARM固件,SBI固件更合规、可靠;但现有版本仍存在启动正确性未验证、PMP(physical memory protection)物理地址访问等安全漏洞。为此,提出了定理证明驱动的闭环形式化验证框架,开发经形式验证的SBI固件——SeSBI,并结合Dafny与Isabelle/HOL,以分层策略实现对启动过程的形式验证。为提高验证效率,提出RISC-V硬件模拟策略,统一建模固件与硬件的交互,从而显著降低验证开销。最终成功验证了SeSBI固件启动过程的功能正确性。结果表明,SeSBI以更简洁的代码实现SBI标准启动过程接口,并具备高度可靠性,为RISC-V生态系统提供了经形式验证的可信SBI固件实现。未来工作将扩展验证范围至更多高级属性,并优化验证工具以提升效率。 展开更多
关键词 RISC-V SBI固件 形式化验证 定理证明 功能正确性
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基于定理证明的UML多视图模型良构一致性验证方法
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作者 吴润方 杜晔 黎妹红 《计算机应用研究》 北大核心 2026年第2期577-587,共11页
针对复杂系统中UML多视图模型良构一致性验证的难题,提出了一种融合结构映射与定理证明的双层验证框架,以系统性地解决跨视图语义交织与结构耦合引发的建模质量风险。该方法通过结构映射验证算法(SMIVA)自动抽取3种视图模型间的结构匹... 针对复杂系统中UML多视图模型良构一致性验证的难题,提出了一种融合结构映射与定理证明的双层验证框架,以系统性地解决跨视图语义交织与结构耦合引发的建模质量风险。该方法通过结构映射验证算法(SMIVA)自动抽取3种视图模型间的结构匹配关系,生成良构一致性断言集以保障类型、命名与拓扑闭合性;同时,基于交互式定理证明器Coq构建形式化断言体系,将行为语义与状态迁移转换为可判定命题,实现语义一致性的逻辑推导。实验以电子商务系统为例,完成了13条良构一致性约束定理的形式化证明。结果表明,该方法能有效提升断言提取的覆盖性、自动化验证能力和验证效率,对提升UML建模质量具有重要意义。 展开更多
关键词 UML模型 多视图一致性 结构映射 定理证明 形式化验证
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多步随机观测滞后和丢包系统极大极小鲁棒Kalman滤波
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作者 杨春山 赵颖 +2 位作者 刘政 丘源 经本钦 《电子与信息学报》 北大核心 2026年第2期752-761,共10页
该文研究了多步随机观测滞后和丢包系统的极大极小鲁棒Kalman滤波问题。系统噪声方差不确定但有已知保守上界,传感器到估值器的多步随机观测滞后和丢包通过一组概率已知的伯努利分布随机变量描述。利用哈达玛乘积改进模型转换方法,设计... 该文研究了多步随机观测滞后和丢包系统的极大极小鲁棒Kalman滤波问题。系统噪声方差不确定但有已知保守上界,传感器到估值器的多步随机观测滞后和丢包通过一组概率已知的伯努利分布随机变量描述。利用哈达玛乘积改进模型转换方法,设计了极大极小鲁棒时变Kalman估值器。利用矩阵初等变换、盖尔圆盘定理和哈达玛乘积定理证明了广义李雅普诺夫方程解的半正定性,进而应用矩阵分解和李雅普诺夫方程方法证明了所设计估值器的鲁棒性,即对所有容许的不确定性,确保实际估计误差方差有最小上界。给出时变广义李雅普诺夫方程存在稳态唯一半正定解的条件,进而设计了鲁棒稳态估值器。证明了时变和稳态估值器的按实现收敛性。仿真实例验证了其有效性。 展开更多
关键词 多步随机观测滞后 丢包 哈达玛乘积 盖尔圆盘定理 极大极小鲁棒滤波
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